vfs_fruit: tmsize prevent overflow Force the type during arithmetic in order to preve...

vfs_fruit: tmsize prevent overflow Force the type during arithmetic in order to prevent overflow when summing the Time Machine folder size. Increase the precision to off_t (used for file sizes), leave the overflow error traps but with more precise wording.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13622
Signed-off-by: Art M. Gallagher <smblock@artmg.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Sat Mar  7 01:37:31 UTC 2020 on sn-devel-184